PITTSBURGH – The Pirates' comeback ended when rookie Mike Crotta lost control.
Crotta walked three of the four batters he faced in the seventh, including a pass to Seth Smith with the bases loaded to force in the go-ahead run in the Colorado Rockies' 6-5 win over Pittsburgh on Sunday.
The loss capped a 1-3 opening home series for the Pirates, dropping them to 5-5 after beginning the season by winning four of six on the road — a start that had Pittsburgh fans hoping this squad could finally end a string of 18 straight losing seasons.
"Tough day," said Crotta (0-1), who was charged with the first run of his career. "I just didn't execute my pitches; that's my job. You come in and got to get outs and it's tough to get outs when you walk people."
James McDonald settled in after allowing six of the first eight batters to reach, allowing the Pirates to score five unanswered runs before they went hitless over the final five innings.
All four batters who faced Crotta reached base after he relieved McDonald with two outs and a runner on with Pittsburgh clinging to a 5-4 lead in the seventh. Jason Giambi's RBI single tied the game.
Pittsburgh had only one baserunner after the end of the fourth inning — a Jose Tabata seventh-inning walk. Tabata stole second, but cleanup hitter Lyle Overbay struck out looking to end the threat.
"We just got into a situation where we didn't continue hitting," Overbay said. "We didn't get that killer instinct and get that (big hit)."
The Pirates scored 14 runs in the equivalent of 4½ games — including a 14-inning victory Friday — on 28 hits in 41 innings.
"Can we improve on offense? Yes, we can," manager Clint Hurdle said.
Colorado's bullpen was nearly flawless and the Rockies improved to 6-2 — their second-best start in franchise history. If not for two extra-inning losses, they'd be unbeaten.
"We're solid, it doesn't matter if we play at home or on the road," said closer Huston Street, who got his fourth save with a perfect ninth. "We expect to win."
Jose Lopez hit a three-run homer and Smith had an RBI single in the first inning for the Rockies, who have been alone in first place in the NL West five straight days for the first time since 2006.
Last season, the Rockies were awful on the road, posting a 31-50 record.
"There were a lot of things we didn't do well on the road last year," manager Jim Tracy said. "So we went back to the drawing board in spring training and brought up bullet points as far as 31-50 — why did it happen? We have certainly addressed some things. We've done a better job of executing."
Jhoulys Chacin (2-0) allowed four earned runs and seven hits in six innings as Colorado's starters improved to 5-0 this season. But they wouldn't be unblemished if not for the Rockies' relievers. Felipe Paulino, Matt Reynolds, Matt Lindstrom and Street combined for three hitless, scoreless innings.
"Our bullpen was terrific," said Tracy, who had to be creative the past two days after using eight pitchers in Friday's 14-inning loss.
McDonald managed to stay around until the seventh after the rocky first. He has had nice success against Colorado, recording three of his nine career wins against the Rockies.
But whatever comfort the right-hander had against them wasn't evident in the first when he struggled with his control, and the Rockies pounced with Lopez's second homer, a shot into the left-field seats that dropped the Pirates into a 4-0 hole.
"I just kind of settled down and kind of had a talk to myself," McDonald said. "'You need to really pick it up; keep your team in the game. They got those runs and that's all they're getting.' I kind of had to motivate myself to hold that game and keep it close. ... I thought like that and went on from there."
McDonald threw 103 pitches in his second start of the season after being limited by an injury to his left side during spring training.
"Huge step forward," Hurdle said. "He did an outstanding job for us today after the first inning."
Overbay had two RBIs and Jose Tabata was on base three times — extending his hitting streak to 10 games — for the Pirates, who scored three in the third and passed Colorado with an unearned run in the fourth.
NOTES: Rockies ace Ubaldo Jimenez threw a bullpen session without any trouble. Tracy said Jimenez, who is on the 15-day disabled list with a cut finger cuticle, will next pitch in Scottsdale, Ariz., on April 13. ... The Pirates finally get a day off Monday. They were the only team in the majors to play the season's first 10 days without a break. ... Colorado has outscored its opponents 14-1 in the first. ... Rockies LF Carlos Gonzalez didn't start because of flulike symptoms. He grounded into a double play as a pinch-hitter in the ninth.